It states that the mass transport of sand is proportional to the third power of the friction velocity.
Under steady conditions, this implies that mass transport is proportional to the third power of the excess of the wind speed (at any fixed height over the sand surface) over the minimum wind speed that is able to activate and sustain a continuous flow of sand grains.
The formula was derived by Bagnold[1] in 1936 and later published in his book The Physics of Blown Sand and Desert Dunes in 1941.
[2] Wind tunnel and field experiments suggest that the formula is basically correct.
is friction velocity proportional to the square root of the shear stress between the wind and the sheet of moving sand.